Fire protection using water from potable water system shall be equipped with ________ check valves, one of which may be an ________ check valve.

Fire protection using water from potable water system shall be equipped with ________ check valves, one of which may be an ________ check valve.

• A. Two check valves, one may be an alarm check valve
• B. One check valve
• C. Three check valves
• D. Four check valves

Answer: (A)

When a fire protection system uses water from the potable supply, backflow prevention is essential to keep that potable water from getting contaminated. The standard approach is to run water through two check valves in sequence. This two-check arrangement provides redundancy: if one valve doesn’t seal perfectly, the other still blocks any reverse flow. An alarm check valve is a type that can be one of these two valves and adds an alarm signal when the valve opens due to flow, giving a notice if the system is drawing water or if a valve is not sealing properly. That combination—two checks, with the option for one to be an alarm check valve—meets typical requirements without overcomplicating the system. The other options don’t provide the necessary redundancy or use more parts than required for this standard setup.

When a fire protection system uses water from the potable supply, backflow prevention is essential to keep that potable water from getting contaminated. The standard approach is to run water through two check valves in sequence. This two-check arrangement provides redundancy: if one valve doesn’t seal perfectly, the other still blocks any reverse flow. An alarm check valve is a type that can be one of these two valves and adds an alarm signal when the valve opens due to flow, giving a notice if the system is drawing water or if a valve is not sealing properly. That combination—two checks, with the option for one to be an alarm check valve—meets typical requirements without overcomplicating the system. The other options don’t provide the necessary redundancy or use more parts than required for this standard setup.